14 — SEA TRAVEL SYSTEM (5e / 2024)

Status: Rev 004 — Core engine + event set + crew points + Alarm escalation + provisions/water economy Dependencies: 04_Ekipman (ship stats), 07_DM_Araclari (travel/encounter), 13_Olay_Sistemi (event engine philosophy — TD/CR separation, d100 luck die, Alarm escalation) Language: English | System: D&D 5e 2024

0. DESIGN PHILOSOPHY

This system rests on three things that make sea travel feel different from land travel: the ship being an object (it takes damage, it can sink), the crew being a resource (it produces actions, it depletes), and the sea having its own rhythm (weather + route shape the texture of every turn).

The system carries two core insights from the Event System (file 13) to sea:

• TD and CR are independent. The event's tone (Danger Level 0–5) and the encounter's power (Region CR) are separate parameters. Calm-but-deadly waters (low TD, high CR) or chaotic-but-weak waters (high TD, low CR) can both be built.
• One die, dual function. The Voyage Die (d100) produces both movement and events — a single roll at the table delivers the texture of the voyage.

Layering principle: Not all four tension axes are actively tracked every turn. Weather & Route is always open (the texture of the voyage). Ship Integrity & Crew are status trackers that only kick in when an event triggers them. This keeps the system rich but light.

1. CORE LOOP

Each voyage turn proceeds in this order:

1. Determine Weather — Determine the turn's weather (§2). Weather applies +1 / 0 / −1 modification to this turn's TD and affects movement.
2. Roll the Voyage Die — Roll d100 against the modified TD (§3). Output: movement progress + event result (clean / minor / major).
3. Event Resolution — If there's an event, draw from the route type's table (§5). If it's an encounter, scale with Region CR.
4. Ship Turn — If a status is active, intervene with crew action points (§4).

Variable scale (zoom): Normal voyaging is abstract — one turn can represent one "leg" (half a day, a day, DM's call). When a major event erupts, the system zooms in: the turn now runs hourly/scene-based until the crisis resolves. Once the crisis ends, it zooms back out.

2. WEATHER & SEA STATE

Weather is determined at the start of the turn and is an independent input (not the event's outcome, but TD's modifier). This prevents circular dependency: weather → TD → event flows one way.

Weather continuity (suggestion): Instead of rolling weather fresh every turn, running it with a ±1 shift from the previous turn gives a more realistic sea feel (a storm doesn't end abruptly). DM's choice.

3. THE VOYAGE DIE (d100)

Roll d100 against the modified TD (0–5). The threshold table below gives the event result.

Validated distribution (20,000 sims, mixed weather): At TD0, event rate is ~28% (mostly minor); at TD5, ~72% (majors rise to 28%). Major events always stay a "special moment." → Calibration: matches the S-curve target.

Movement: The weather modifier determines movement — Full+ / Normal / Slow. Concrete distance is calculated from ship speed × time scale (see 04_Ekipman ship speed table).

Natural 100 (Fate): With the same logic as the Nat-20 Fate List in the Event System (file 13), rolling 00 (100) on the d100 triggers a special "sea fate" (rare, dramatic event — separate list planned).

4. SHIP INTEGRITY, STATUSES & CREW

4.1 Ship Base

Ship stats are taken from the PHB table in 04_Ekipman (AC / HP / Damage Threshold / Crew / Cargo). These are the base — a status layer stacks on top (the same principle as "data is Normal, difficulty is the layer" from the boss system).

4.2 Statuses (Status Effects)

Status = an active crisis riding on the ship (fire, flooding, broken rudder, torn sail...). Each status has an extinguish DC and a severity level (starts at 1).

• Active status ceiling: 4. At most 4 statuses at once. (The sea equivalent of the Event System's (file 13) "2 combat ceiling" logic — to keep the table from drowning.)
• Severity: If extinguishing fails, the status can worsen; severity makes the DC +2 harder.

4.3 Crew = Action Point Pool

Each turn, the crew grants the ship action points. Points are spent on extinguishing statuses, maneuvering, repairs, etc.

• Base points: 2 — comes from the player characters, independent of the crew. (The safety floor that breaks the death spiral.)
• Crew points: 1–5 depending on ship type — the "ship stats are the base" principle applies to the crew as well. Full-crew crew points are derived from the ship's crew count:

Total turn points = base 2 + crew points = range 3–7. Diminishing returns principle: Action points don't represent "how many people are there," but "how many effective interventions can be made in one turn" — 80 people can't put out a burning sail at once, only a few teams can work in tight quarters. This is why the ceiling is fixed at 5.

Important: This table gives the full-crew value. As the crew shrinks, this portion drops proportionally (the base of 2 always remains). E.g., a Longship (base 4) drops to ~2 at half crew. Since calibration was done on the Sailing Ship (20 people → 3 points), previous simulations remain valid.

Status extinguishing cost:

• 1 point → normal roll (d20 + relevant ability) vs status DC.
• 2 points → advantage roll (same extinguishing check, take the higher of two d20s).

4.4 Failure Resolution (consistent with the Critical System)

The difference between the extinguishing roll and the status DC is what matters — this is a direct sibling of the "5+ difference" threshold in your Critical Success/Failure system:

This structure ensures no single failure is catastrophic: spread is rare (only on a big miss), most failures just worsen the status.

Validated balance (2,000 sims/tier): With base 2 + crew 3 (Sailing Ship reference) + advantage cost 2 — light crisis ~77% survival, moderate crisis ~65%, heavy crisis ~46%. Crew loss feels proportionate to the tier (22% → 62%) but doesn't by itself create a death spiral. → Calibration approved.

4A. PROVISIONS & WATER ECONOMY

In this world, voyages last months and the seas are desolate. Provisions is the system that turns distance from an abstract number into tension. Design principle: doesn't punish the reasonable player, hits the negligent one. Punishment is rare, tension is constant — this is decision pressure, not bookkeeping drudgery.

4A.1 Single Counter: Provision Day

Provisions are tracked with a single abstract counter: Provision Day = how many more days the ship can go. Calculated once per voyage, events deplete it. (Same lightness philosophy as weather = single die — a single counter in the background that comes to the fore when it turns critical.)

Starting amount: Reasonable preparation = voyage duration × ~1.15. If the party loads less, they take on their own risk (they gain cargo space but tension rises).

• Each day −1 Provision Day.
• Some events (Dead Calm, spoilage, theft) deplete extra (~30%/day chance of −1 to −3).

4A.2 Trade Link: Base + Extra

A two-layer store:

• Base provisions: A fixed base store specific to each ship type (crew doesn't starve, short routes are troublefree). Independent of cargo.
• Extra provisions: The additional provisions needed for a long/desolate voyage, which takes up space from the trade cargo hold (see Trade §1.3 capacity). This creates the merchant's "how much goods, how much provisions" decision — provisions compete with profit.

4A.3 Graduated Warning Chain (soft)

As provisions dwindle, crisis escalates, it doesn't strike suddenly. Each stage gives the player a decision window:

Why slow exhaustion: In the 2024 rules, exhaustion is harsh (−2 per level, death at 6). Piling it on immediately when provisions run out creates a death spiral (the provisions version of the crew/action point spiral). Slow accumulation prevents this.

Validated balance (3,000 sims, long voyage): With provisions multiplier 1.15 + 30% event chance — a negligent party is genuinely strained (avg 1.0 exhaustion, 14% heavy crisis), a reasonable party arrives safely (avg 0.0 exhaustion) but experiences stopover-pressure tension for ~30% of the route. Tension is constant, punishment is rare. → "Tension without breaking the player" goal hit.

4A.4 Exit Paths (player intervention)

A provisions crisis is not a death sentence, it's pressure — the player can intervene at every stage:

• Stopover: Put in at a port/land to resupply (if the route allows it; desolate waters never have a port).
• Half rations: Slow consumption (at the cost of morale — crisis-event risk).
• Fishing: Catching fish at sea, a partial lifesaver. 40% chance of +1–2 Provision Days (not guaranteed — hope, not a guaranteed solution; tension is preserved). The Fishing profession (Trade §3.2) becomes here not "earning money" but a "survival" tool. A natural exit in stranding events like Dead Calm.
• Magic: Create Food and Water, Control Water, etc. — for parties with high magic access (the world is magic-restricted, so this is a privilege).

4A.5 Difficulty Modifier Link

The severity of the provisions crisis (exhaustion speed, event frequency, starting multiplier) will be tuned via a modifier table tied to the difficulty layer. The core is soft; "Deadly" mode makes provisions a real threat. [COWORK — modifier table to be filled in] (same "data is Normal, difficulty is the layer" principle as the boss difficulty system).

5. ROUTE TYPES

The route determines the base TD and which event table is used. Region CR (encounter power) is independent of the route — the DM sets it separately.

5A. ALARM ESCALATION

The sea adaptation of the Alarm principle from the Event System (file 13): a recurring threat is not blocked, it's escalated. As you leave traces in a region, a pursuer notices you and comes after you — narrative escalation instead of a hard block.

Region-Bound Alarm Type

Each region has its own Alarm type; it does not convert to another type (consistent with TD/CR independence — a monster-free region doesn't produce a monster Alarm):

Reactive vs. Proactive — the critical distinction: In authority waters, if you travel clean, Alarm stays at 0; the counter only starts with your own action (looting, combat, loud magic). In proactive regions, even lingering accrues Alarm — hunters/entities naturally hunt there.

Counter: 0–5

Alarm rises from 0 to 5. Tiers unlock gradually (the boss system's "structural change > numeric multiplier" principle):

How Alarm Rises (validated calibration)

Combat & action link (Naval Combat §6C): Combat outcomes and actions also affect Alarm. Pirate/authority combat leaves Alarm depending on region+witnesses (monster combat leaves none); legitimate action (licensed bounty hunting, clearing a threat) lowers Alarm, unlawful action (smuggling, looting) raises it. Behavior determines Alarm, not profession.

How Alarm Falls

• Leaving the region: Moving to different waters/route lets Alarm drop over time (suggestion: −1 per clean leg).
• Losing/defeating the named pursuer: If the threshold-5 pursuer is eliminated, Alarm resets to 0–1.
• In authority regions: Legitimizing (paying a fine, pardon, forged papers) can rapidly lower Alarm — narrative-dependent.

Validation (5,000 sims/cell, 8-turn voyage)

Named-pursuer encounter rates matched the design targets:

• Authority + clean play: 10% (rare as intended — an honest trader stays unnoticed).
• Authority + looter: 85% (chased for cause).
• Proactive + clean: 37% (there's risk but it's avoidable; an escape strategy matters).
• Proactive + looter: 95% (certain pursuit).
• Profile separation holds in every region — clean < balanced < looter — the system behaves "fairly."

6. CORE EVENT SET (Rev 001)

This set is a starting example that tests every part of the engine at least once: status-spawning, crew-testing, pure encounter, navigation, and social/decision events. Each table will be expanded further in the future. Every event carries a [Minor] or [Major] tag; the Voyage Die result determines which one is drawn.

6.1 COASTAL WATERS (Base TD 1)

K1 — Customs Patrol [Minor · Social/Decision] A harbor patrol stops your ship, demands cargo and papers. Decision: bribe (Persuasion/Deception vs DC 13), flee (maneuver race if weather isn't Slow), or submit to inspection (risk if carrying contraband). Engine test: a social event, resolvable without turning into an encounter; failure produces a complication, not "stupidity."

K2 — Rocky Shoal [Minor · Navigation → Status] An uncharted shoal in a misty coastline. Helmsman Navigation check (DC 14). Success: passed clear. Failure by 1–4: the ship scrapes → Flooding (severity 1) status. Failure by 5+: a hard strike → Flooding + ship HP damage. Engine test: navigation → status birth, DC-difference threshold in play.

K3 — Pirate Sloop [Major · Encounter] A fast pirate boat approaches. Crew + captain scaled to Region CR. Escape (speed/weather), negotiate (demand: half the cargo), or fight. Engine test: pure encounter, Region CR independence — even in coastal waters, a deadly pirate (high CR) is possible.

K4 — Sunken Wreck [Minor · Decision/Reward] A half-sunken shipwreck. Looting is tempting but costs time + risk. Investigation (DC 13) for valuable cargo; on failure the wreck suddenly shifts, risking the diving crew member. Engine test: risk/reward decision, optionally spends the crew resource.

6.2 OPEN SEA (Base TD 3)

A1 — Sail Fire [Major · Status Chain] Lightning or an accident sets the sail ablaze. Starting Fire (severity 1, DC 14) status. Each turn it's not extinguished: 1–4 difference → worsens (DC+2, movement drops to Slow); 5+ difference → spreads → Mast Ablaze (new status). If not extinguished, ship HP starts burning. Engine test: status severity + spread chain, the main test of the action point economy.

A2 — Dead Calm [Minor · Resource Pressure] Wind dies completely; the ship makes no progress by oar, or none at all. Movement stops, provisions/water pressure begins. If prolonged, crew morale (abstract) may drop. Solution: rowing (crew points), magic (Control Water etc.), or waiting for a weather roll. Engine test: directly hits the movement axis, "slow" state becomes a tension source.

A3 — Deep Water Hunter [Major · Encounter + Status] A sea monster (scaled to Region CR — giant octopus, sahuagin raid, plesiosaur, etc.) attacks the ship. Both a creature encounter and a Hull Damage/Flooding status risk (from grappling). Engine test: encounter + status combination, two subsystems running simultaneously.

A4 — Drifting Course [Minor · Navigation] An unexpected current pushes the ship off course. Navigation (DC 15) to correct; failure turns progress into a "lost turn" or drifts into a new (unwanted) region → DM may change Region CR. Engine test: navigation → route/CR change, tied to the variable scale.

6.3 CURSED / UNKNOWN WATERS (Base TD 5)

L1 — Choking Fog [Minor→Major · Atmosphere/Navigation] An unnatural fog envelops the ship. Visibility zero, Navigation at disadvantage. Within the fog, the Voyage Die gets +1 TD next turn (already at the TD5 ceiling). Sounds from the fog (eerie) test crew morale. Engine test: a weather/atmosphere event affecting the next turn, TD-ceiling behavior.

L2 — Ghost Ship [Major · Encounter/Social Hybrid] An abandoned(?) ship emerges from the fog. Approaching: loot + information is tempting, but there's a curse/ghost crew (Region CR) risk. Social option: "negotiate" with the ghosts (passage in exchange for a task/oath). Engine test: encounter interwoven with social, an avoidable major event.

L3 — Vortex of Fate [Major · Supernatural Status] A giant whirlpool pulls the ship in. Each turn: captain's Vehicle/Strength check (DC 16) to break away. Failure margin can produce Flooding + Broken Rudder statuses. A Natural 100 Voyage Die here can trigger the fate of being "dragged to another sea/plane." Engine test: high-DC supernatural crisis, Nat-100 fate link, multi-status pressure (test of the ceiling of 4).

L4 — Beckoning Voice [Minor · Social/Willpower] A voice from the water (siren/entity) calls to the crew. Those affected make a Wisdom save (DC 14); on failure, a crew member feels an urge to "jump overboard" — but the character isn't made foolish: even one gripped by the urge acts on a reasonable pretext (your social-failure principle). Can be turned back by captain's intervention. Engine test: willpower/social event, crew-loss risk tied to the point economy.

7. REVISION HISTORY

• Rev 001 — Core engine established: core loop, weather system (d6, ±1 TD mod), Voyage Die (d100 × TD0–5 threshold table), ship status system (severity/spread, DC-difference threshold), crew action point pool (base 2 + crew 3, advantage cost 2), 3 route types, 12 example events. Two core systems validated with Python simulation (action point economy: 2,000 sims/tier; Voyage Die distribution: 20,000 sims).
• Rev 002 — Crew action points converted from a fixed "3" value to a ship-type-dependent tier table (1–5). Reason: PHB crew counts vary wildly (Rowboat 1 – Galley 80), a fixed value contradicted the "ship stats are the base" principle. The tier function was chosen over log2/square-root candidates: keeps Sailing Ship at 3 to preserve existing calibration, caps at 5 for large ships via the diminishing-returns principle. Previous simulations remain valid (Sailing Ship was the reference).
• Rev 003 — Alarm Escalation system added (§5A). The sea adaptation of the Event System's (file 13) Alarm principle: region-bound Alarm type (Authority/Hunter/Curse), reactive-proactive region distinction, 0–5 graduated counter (1-2 frequency, 3-4 CR, 5 named pursuer), mixed rise sources and fall rules. Calibrated with two simulation passes: the first attempt (generous rise) violated design intent — even clean play in authority waters reached the pursuer 56% of the time; once rise sources were trimmed and the tiers extended to 0–5, the target was hit (authority+clean 10%, authority+looter 85%, proactive+clean 37%, proactive+looter 95%). 5,000 sims/cell.
• Rev 004 — Provisions & Water Economy added (§4A). Single abstract counter (Provision Day), graduated warning chain (stopover pressure → crisis events → slow exhaustion), trade cargo link (base + extra provisions), fishing as a partial lifesaver (40% chance), difficulty modifier link [COWORK]. Calibrated with simulation (3,000 sims): the first attempt was too soft (1.3× provisions abundance → no tension at all, even a negligent party arrived fine); dialing the provisions multiplier to 1.15 + 30% event chance found the sweet spot — a negligent party is strained (avg 1.0 exhaustion, 14% heavy) while a reasonable party arrives safely (avg 0.0) but experiences stopover-pressure tension for ~30% of the route. "Punish negligence, not reasonable play" principle validated.

8. NOTES FOR THE NEXT SESSION (Gaps)

• Event table expansion: Expand each route to ~20+ events; separate minor/major d100 subtables.
• Nat-100 Sea Fate List: A separate, dramatic event table like the Event System's (file 13) Nat-20 Fate List.
• Named pursuer catalog: Ready-made named pursuer statblocks for each region (navy captain, named sea monster, ghost ship) — to be used when Alarm 5 triggers.
• Crew morale: Currently abstract; a light tier system (mutiny threshold) could be added if desired — but simulation testing is a must given death-spiral risk.
• Difficulty layer: Adapting the Easy/Normal/Hard/Deadly tier from the boss system to the sea (via TD and Region CR).